The present invention relates to a screwless hinge of an eyeglass frame.
As hinges for eyeglasses, there are proposed those described in the following.
The Japanese Utility Model Application Laid-Open No. 7-23320 proposes a hinge in which a fit member 34 formed of metallic wire materials at the tip end of a temple is in planar or linear contact with a spherical, columnar or disc-like coupling member 31 having an annular groove.
FIG. 3 shows an example in which the coupling member 31 provided on a wire material 32 on the rim side takes a columnar form. The Coupling member 31 is secured by the wire material 32 passed through the center of the column.
A groove 33 is formed on the coupling member 31 in the circumferential direction about an approximate center in the direction of thickness of the coupling member 31. The fit member 34 is fitted in this groove 33 to be rotatable and the temple is folded or unfolded upon rotation of the fit member 34. Then, a stopper 35 is provided by bending the tip end of the wire material 32 for limiting this rotation so as to prevent the temple from being unfolded too wide.
The Japanese Patent Application Laid-Open No. 8-50264 discloses a hinge which is entirely formed of linear members (see FIGS. 4A to 4C).
In this case, as shown in FIG. 4A, the hinge is entirely formed of wire materials, and one end of a coupling member 41 which is provided on the rim side has an annular structure. On one end of a temple 43, there is formed a support member 44 which is to be attached to the annular portion of the coupling member 41 to be rotatable.
FIG. 4B is a schematic view for showing an eyeglass frame, seen from the lateral side, in a state in which the support member 44 is attached to the coupling member 41. FIG. 4C is a view showing this state seen from above.
In a state in which the temple 43 is completely unfolded, a part of the annular part of the coupling member 41 serves as a stopper 42, so as to limit an unfolding movement of the temple 43.
A hinge disclosed in the Japanese Patent Application Laid-Open No. 10-20260 comprises, as shown in FIGS. 5A and 5B, comprises a bracket 51 which is obtained by dividing a wire material serving as the coupling member into upper and lower parts. One end of the bracket 51 is secured to a rim 52. The other end of the bracket 51 is in an annular structure when the eyeglass frame is seen from above. In addition, one end of a temple 53 is also in an annular structure, and a cylindrical fit member 54 is secured to the inner side of this annular portion.
The wire material for forming the annular structure of the temple 53 is coupled between the two wire materials of the bracket 51 to be rotatable around the fit member 54.
The fit member 54 is provided with a stopper 55 for limiting folding and unfolding movements of the temple 53. The folding or unfolding movement of the temple 53 is stopped at a position at which this stopper 55 is brought into contact with the bracket 51 in the folding and unfolding movements.
FIG. 5B is a view for schematically showing the bracket 51 and the fit member 53 removed off from the frame.
The screwless hinges disclosed in the above-described prior arts have their own problems.
The hinge disclosed in the Japanese Utility Model Application Laid-Open No. 7-23320 (see FIG. 3) is in a state in which the stopper 35 for limiting rotation is protruded outward from the eyeglass frame, which does not render an attractive appearance. Further, there arises a problem that the stopper 35 may catch clothes or the like. Further, in this structure, it is difficult to position the stopper 35, and there may arise problems that the right and left temples are unfolded in different amounts, and that the initial angle can not be maintained in the course of use owing to deformation, or the like, of the stopper 35. Furthermore, the coupling member 31 and the fit member 34 are in linear contact, which brings about a problem that the groove 33 of the coupling member 31 is abraded by friction.
A hole of the support member 44 of the hinge disclosed in the Japanese Patent Application Laid-Open No. 8-50264 (see FIGS. 4A to 4C) is a so-called clearance hole, and the resisting force in rotation in this case is caused only by a friction due to plane contact with the coupling member 41, which may make the folding and unfolding movements unstable.
When the temple 43 is to be attached to the frame, an unnecessary force may be applied on the coupling member 41. Thus, an unstable contact of the contact surface (a so-called one-side contact) may be brought about due to deformation or the like of the coupling member 41. Further, this hinge is formed only of wire materials, so that the coupling position of the temple 43 may be displaced downward by the weight of the temple 43 itself.
Furthermore, in case of the hinge disclosed in the Japanese Patent Application Laid-Open No. 10-20260 (see FIGS. 5A and 5B), in order to bring the wire material having the annular structure of the bracket 51 into linear contact with the fit member 54, it is required to align the both members to each other in such a manner that the both members should be rubbed uniformly. Accordingly, it is naturally expected that an area of contact becomes large and a smooth sliding movement is gradually difficult to be obtained with the elapse of time. Then, these conventional screwless hinges have the common problem that the contact area at the fit portion in each of the hinges is large so as to cause a problematic friction between the members upon folding and unfolding movements of the hinge. Then, there is another problem of the degraded rotational torque performance which is caused by deterioration due to this friction. Further, there is also a problem of difficulty to obtain a high precision in working the fit member due to an area of contact between the coupling member and the fit member at the fitting time.
The present inventors have found that the above problems can be solved by improving the form of a coupling member to be secured to the rim and a method of contact with a temple to be coupled to this temple.
According to a first aspect of the present invention, there is provided eyeglasses provided with hinges each comprising:
(a) a pair of lenses; and
(b) a coupling member formed of wire material, having a curved portion at one end thereof and being secured to the lens or a rim at the other end, and a fit member provided at one end of a temple,
wherein the fit member has a circumferential groove and the curved portion is fitted in the groove to be rotatable, and
the coupling member and the fit member are brought into contact with each other at least at two points.
It is preferable that, in these eyeglasses, an area of contact between the coupling member and the fit member at the above contact points is not more than two thirds as large as the circumference of the groove.
According to a second aspect of the present invention, there is provided an eyeglass frame with hinges each comprising:
a coupling member formed of wire material and having a curved portion at one end thereof and being secured to a lens or a rim at the other end; and
a fit member provided at one end of a temple,
wherein the fit member has a circumferential groove and the curved portion is fitted in the groove to be rotatable, and
the coupling member and the fit member are brought into contact with each other at least at two points.
It is preferable that, in this eyeglass frame, an area of contact between the coupling member and the fit member at the above contact points is not more than two thirds as large as the circumference of the groove.
According to a third aspect of the present invention, there is provided a hinge comprising:
a coupling member formed of wire material and having a curved portion at one end thereof and being secured to a lens or a rim at thee other end; and
a fit member provided at one end of a temple,
wherein the fit member has a circumferential groove and the curved portion is fitted in the groove to be rotatable, and
the coupling member and the fit member are brought into contact with each other at least at two points.
It is preferable that, in this hinge, an area of contact between the coupling member and the fit member at the contact points is not more than two thirds as large as the circumference of the groove.